Flotation-machine



T. A. JANNEY.

FLOTATION MACHINE.

nrucmon msu me. 21,' |916.

1,342,115. Patented June 1,1920.

6 SHEETS-SHEET l.

T. A. JANNEY.

FLoTATloN MACHINE. APPLICATION FILED JAN. 2.7 |916.

11,842,115. l l PatentdJune 1,1920.

6 SHEETS-SHEET 2.l

T. A. JANNEY. FLOTATION MACHINE.

APPLICATION FILED JAN. 27. 1916.

Patented Jane 1, 1920.

O o o o o o o o o ,o

0 O 0, 0 O O O O O O Wyss.' Lu/enfans T. A. J A NNEY. FLOTATION MACHINE.V

ARPLlcATloN FILED 1AN.27.1916.

3 1i -1 if Zwaan-j ma# hay Patented June 1, 1920,11,

s SHEETS-SHEET 4.

T. A. JANNEY.

v FLOTATION MACHINE.

APPLlcAloN FILED mm2?. Isle.

LMQAM. PatemwdlJune 1, 1920.

6 SHEETS-SHEET 6.

Patented mw 1,

T. A. IANNEY.

FLOTATION MACHINE.

APPLICATION FILED JAN. 27| 1916.

. process.

UNITED STATES THOMAS A. J' ANNEY, OF GARFIELD, UTAH.

NOTATION-MACHINE.

Specification of Letters Patent.

Patented June 1, 1920.

- Application led January 27, 1916. Serial No. 74,561.

To all whom t may concern.'

Be it known that I, THOMAS A. JANNEY., a citizen of the United States, residing at Garfield, in the county of Salt Lake and State of Utah, have invented certain new and useful Improvements in Flotation- Machines, of which the following is a specification. f

This invention relates to flotation processes for concentrating ores of the general type in which a freely flowing pulp is agitated with oil, or other frothing agent, and other re-agents as circumstances demand, and in which the metalliferous part of the ore'is floated and removed from the pulp while in a more quiescent condition in another part of the apparatus. l

The object of the present invention is to improve the apparatus used for this purpose, an important feature being the addition of means for introducing air, or other gas, as may be found advisable, in a finely divided state into the pulp when in its more quiescent condition, after said pulp has previously beensubjected to mechanical agitation and aeration. This feature effects amore complete separation of the 'mineral particles from the gangue than now prevails, this being dueto the combined action of mechanical agitation and the subsequent application of air to the pulp. The immediate introduction4 of rair after mechanical agitation increases the effect by adding volume the foam or froth, and expedites, as well as improves, the entire Circulation of the pulp repeatedly through the separation chamber and agitation cell is'provided for, thereby removing the metalliferous particles, the separator chamber permits the heavier portion of the gangue and'worthles's material to .be slowly with the. duct leading to this orifice is an upwardly eXtendin pipe which allows the lighter portions o the gangue' to escape, the upper end of said pipe being adjustable in height to regulate the level of the pulp in vthe separation chamber. This level is maintained between the air-charging means and the overflow lip. The overflow lip has a position below the level of the outlet of the agitation vessel, and above the level at which'the air is introduced. The means for introducing air comprises an air basket or thoroughly whilean orifice of restricted size at the bottom" of discharged. Connected box divided .into compartments at different depths below a sloping perforated medium,

which leads downwardly from the outlet of the agitation cell to the lowerV portion of the separating chamber. Means are provided for introducing air to the different chambers in such manner as to regulate the introduction of air into the pulp at various depths in a uniform manner.

The above and other objects will be more apparent in the following specification, when taken in connection with the drawings, and the novel elements and combinations thereof will be set forth in the appended claims.

In the accompanying drawings- Figure 1 is a cross section of the appa- '/ratus through an agitating cell and adjacent vseparating chambers at either side thereof.

Fig. 2 is'a plan view of one of said agitating cells and adjacent separating chambers, together with portions of other cells and chambers in a series. Fig. 2a is a sectional view showing the openings in the agitating cell for connection withthe pipes 32 and 33.

Fig. 3 is a plan view of one of the air baskets, or air-introducing boxes, which have sloping positions in the separating chambers.

Fig. 4 is a cross section thereof, taken substantially on the line 4 4 of Fig. 3.

Fig. 5 is va detail view of a portion of a perforated sheet forming a part of the perforated medium of said air basket.

" Fig. 6 is a detail sectional view of the structure of the air basket, taken on the line 6 6 of Fig. 3.

Fig. Z is another detail sectional view of said structure, taken on the line 7 7 of Fig. 3.

Fig. 8 is a plan view of another of said air baskets.

`Fig. 9 is a sectional view thereof, taken on the line 9 9 of Fig. 8.

v"-to13`igs. land 2, which show the general ar-g rangemento f all of the essentialelements of my invention. It will be understood that. this shows but 'onespecific form, and arrangement of parts, and that it is apparent that wide variations ma be made therefrom without departing romthe invention as defined in the a pended claims.

The agitating c amber 15 is preferablyl cylindrical in form, with an open upper end forming a ldischar e outlet. A rotary shaft 19, axially dispose in said chamber, carries agitators or impellers 17 and 18 fixed thereon, the lowen one-17- having vanes or ,arms 17 a with inclined upper surfaces, said arms being of such length as to rotate within inwardly projecting ribs 27 on the inner wall of said chamber. The upper agitator 18 is similar to the agitator 17, eX- cept that its arms are longer and reach nearly to the yinner surface of the cell 15.

rlhe armsof the a itat'or 18 passover the upper'ends of the r1bs27 ,and beat air into the pulp that is elevated between the ribs by the agitator 17. The level of the pul in the cell in a quiescent condition is pre erably' maintained substantially at or below the -upper ends of the ribs. The agitator shaft 19 is secured at 20-preferably b screw threads-to the lower end of the sha of a vertically disposed motor 21.

Immediately above the open end of the cell which extend through a series of agitating and separating elements, as indicated in.

Fig.v Extending laterally from these frame members are other frame. members or partitions 23c separating the adjacent separation4 chambers. Other wall and frame members 23d on the outer limits of the separating chambers complete the inclosure of said chambers, which receive the pulp from the agitation cells.

A launder 25 discharges the pulp into a I funnel 26 leading through a suitable pipe 26a to the'lower portion of thel agitation cell.- This pipe \is preferably disposed within one of the separating chambers, as shown in Fig. 1.

Vithin the separation chambers,-one of l which is disposed on each side of the agitaltion cell-are disposed inclined airbaskets or boxes 44, having `their upper ends in contact with walls 23b a suitable distance below the, discharge portions 24 of the caps controllingthe liow from Vthe agitation cell.`

vthe gang'ue to the desiredl slow rate.

These air baskets, with perforated tops for the admission of air as will be later de- 'small angle and discharges the overiiowing froth into.a launder 31 running longitudinally of the series of machines. f ne of said launders is disposed at either side of v c l n C sald ser1es, as shown 1n F1 1 and 2, and

carries the froth tothe desired locality forfurther treatment.

Below the air baskets '44 in the separa'- tion chambers are circulation ducts or pipes 32 and 33 leading from the lowermostLportions of said chambers to the lower portion of the agitation cell 154 These pipes are of large capacity, and their purpose is to allow a 'free return of the pulp in said Vchambers to the cell. The innermost ends 34 and 35 of these pipes terminate in front of orifices 34a and 35a in the agitation cell. These orifices are disposed in such relation to the ribs 27 in said cell ,as to prevent interference of the ribs with the inflow of the .cur.

rent.

In the lowermost portions of the separation chambers are disposed outlets 36 leading to ordinary T-pipe fittings 37, in the lower part of which are placed reducing plugs 40, which, in turn, hold porcelain bushings 38, in which is an outlet orifice of relatively small size. The bottom 36a1of said chamber is preferably made of cement or concrete, and slopes uniformly toward the outlets 36. The bushings 38 are held in pla`ce by the flange 39,-and may be easily replaced by bushings of other sizes, having orifices of just such dimensions as willl restrict the outflow of the heavier portionrsnef e rate of outfiow `can thusbe regulated to cause the pulp to flow. repeatedly through the pipes 32 and 33 back to the agitation cell for repeatedoperations upon it a suiicient number of'times to insure thorough removal of the metalliferous particles by the apparatus.`

The heavier portions of the gangue will slowly pass out through the bushing 38 into the tailing -launder 38, while the lighter portions of said gangue will rise in the pipe 41 and overflow at the upper end into the inclined launder 42 `which leads to the tailing launder.' Upon the upper end of the pipe 4l is a threaded sleeve or coupling 43, by which the level of the pulp in the separation chamber may be regulated. This sleeve may be raised or lowered on the pipe 43 by rotating it. The pipe 41 is of suffiporous membrane cient size to give an unrestricted outlet to the pulp and to take care of all pulp which enters through the launder. n

Returning to the air baskets or boxes 44, it will be seen that they comprise separate air chambers 45, 46, and 47, above which are-disposed the perforated sheetsor plates 48, Awith relatively large perforations for supporting the porous sheet or membrane 49 with relatively small perfor-ations or pores. Separate air pipes l50, 51, and 52 lead to the respective chambers 45, 46, and 47, each of said pipes being supplied with a re ulating valve, as shown at 55, 56and 57 hese pipes lead to headers 53, which, in turn, receive their supply of air from the mains54. 'By means of these valves the air in the chambers 45, 46, and 47 may be regulated to produce the desired uniformity of iow through the different depths of pulp above said chambers.

The structure of the air baskets comprises a rectangular box lformed by a bottom 58 and outer walls 59 rising vthere-above. The

chambers 45, 46, and 47 are' separated by partitions60 and 61. Other ribs 62 at right-- angles to saidy partitions are disposed at regular interyals for giving the necessary rigidity to the structure.` To these ribs and partitions, as well as to the. outer walls 59, are secured the perforated sheets 48 and 49 by suitable strips 63 placed above them,and held in place by the bolts 64. The longitudinal strips 63a are preferably .rounded at their upper edges to permit the pulp to .migrate more freely over their upper surfaces. The transverse strips 63b need not necessarily be so rounded.' ln the lower portions of the ribs 62 are placed openings 65 lfor allowing equalization of the air in the different portions of each of the chambers, but no such openings are provided in the partitions 60 and 61 between thechambers themselves. One of the air baskets 44 .is provided with a notch 66 to prevent interference with the inlet pipe 26a leading to the agitation cell. J

In the use and voperation of the present 4invention it will be seen that the ore pulp is supplied to the machine through the launder 25, funnel 26, and pipe 26a to the lower portion of the agitation cell 15. The motor 21 rotates the agitators 17 and 18, the centrifugal force imparted to the pulp causing it to rise between the ribs 27, and causing the lupper agitator 18 to beat, air into the rising pulp and imp el it upwardly and over the open ends of the cell under the cap 23, and downwardly into the separation chambers 16. The air admitted `into the'pulp in said chambers through the porous membranes of the air boxes 44 rises through said pulp and selects the metalliferous particles therefrom,

adding to the froth formed-by the agitation in the. cell 15. 'The agitator in the cell produc'es a large amount 'of froth, which flows over into the separation chambers and floats on the pulp therein, its volume being increased and the separating effect augmented by the air rising from the air baskets. The accumulation of froth causes'it to flow over the lip 30 and downwardly into the launder 31. The heavier particles of the pulp migrate slowly downwardly over the porous membrane ofthe air basket 44, and finally drop over the lower edge of said air basket and downwardly toward the outlet orifice 36. A large portion of said pulp, however, cannot find an outlet, du'el to the restricted size ofthe bushing 38, and the arbitrary adjustment of sleeve 43, and returns through the pipes 32 and 33 to the lower portion o-f the agitation cell. The circulation thus produced throughl the agitation cell andseparation chamber causes repeated operations to be performed upon the same pulp. Finally, the very heaviest particles slowlypass out through the bushing 3 8, while those of lighter weight ascend in the pipe 41, and escape over the upper end of the sleeve 43. By means of the adjustable sleeve 43 the l precise level of the pulp in lthe chambers can be regulated.

In Figs. 11 and 12 are shown a modified form of my improved concentrating apparatus. The air basket 67 in` this form is made with a body of cast metal, with, a' number of compartments to receive the ain below the perforated medium. -This cast metal body is indicated at 67, and rests at its lower edge upon a cleat or rib 68a rigidly secured to the settling box or well 69`in the lowermost portion of the separation chamber. At its upper edge it rests upon a similar cleat 95, secured to the inner wall 753L 105 between the separation chamber and agitation cell. Leading from this well back to the agitation cell 7 5 are they pipes 70 and 71, said pipes being secured at one end to the wall 68 of the well, and at their other ends 110 to the wall 7 5a. Openings through thecell casing at 7 5b lead the pulp to other openings 73 and 74 in the cell lining. The agitation of the pulp in the cell, and circulation thereof from the cellto the separation chamber 115 and back through the pipes 70 and 71, is substantially the same as that previously described in connection with Figs. 1 and 2.

'In the'lowermost part of the well 69 is4 y the outlet 76, leading to the fitting 77, above 120 which rises in a vertical direction the secondary overfiow pipe 78. This pipe is adjusted in the fitting 77 to regulate the level of the pulp in theseparation chamber. In the lower p'art of the fitting is the plug or 125 bushing 7 9,7 containing a small aperture similar to that described in Figs.' 1 and 2.

The outlet" at 7 9a opens into the, launder 80. The overflow from lthe secondary outlet 78 passes into the vertical chute or 130 launder 82, and thence into the launder- 80.

' pulp which is supplied' to thel apparatus, this vfunnel being secured to the thickened unit in the-series.

portion V86 .ofthe air basket body casting. An elbow fitting 85 is also secured to said casting, and forms a continuation of the inlet funnel leading to the lower part -of the agitation cell. Within the agitation cell are the rotary agitators 87 and 88, similar to those previously described, these agitators being secured to the upright shaft 89, which .is driven by the motor 90.

The air chambers are supplied with air through flexible tubes orhose 9.1, each of which is rovided with a controlling valve 94.- Air 1s supplied to said .valve's.from a header 92, which, in turn, is connected with the main 93. The operation of this modified form is in all essential respects similar to that described in connection .with the previous form illustrated in Figs. 1 to 10, inclusive.

In the form'shown in Figs. 1 to 10, in-J clusive, the. tailings in laimder 38a may be led back tothe next agitation cell in the series for retreatment, and so on until the pulp is finally dischar ed from the last In 1' e manner the tailings in launder 80 Figs. 11 and 12, may be led through a number of units in a series.

While I have described my invention with more or less minuteness, and as being embodied in certain'precise forma. yet it will be understood that I do not desire to limit myselfi thereto unduly, or any more than is ointed out in the claims. On the contrary, contemplate all proper changes in form, construction, and arrangement, tle omission of immaterial parts, and the substitution of equivalents, as circumstances may suggest or necessity render expedient.` Y

Iclaim v l. The combination 'in flotation apparatus for ore pul ,of an agitation vessel and a separatingox located relatively close to-V gether and communicating directly with eachl other, means for mechanically agitating the pulp in said vessel to mingle air therewith and propel the pulp into said separating box, and stationary meansA for distributing air in i a finely divided condition into the substantially quiescent pul in said separating box.- In a device o the class described, an agitation vessel for ore pulp contained therefor agitating the ore pulp and for causing a` circulation of said pulp from said vessel to said box through the upperport and back to the vessel through the lower port, and means for introducing air in a finely divided conditioninto the ore pul in said separating box.

3. In a device o the class described, a froth separating box having inlet and outlet openings at the upper and lower parts thereof respectively, means for mechanically agitating ore pulp in contact with air and for supplying said pulp through said inlet opening into said separating box, an air supply chamber having a permeable wall below the level 'of the pulp-fin said box, and means for supplying air t ough said permeable wall to maintain anfupward current of air bubbles through said pulp while said pulp is in a substantially quiescent condition.

4. In a device of the class described, an agitation vessel, a Aseparating box communieating directly with said agitation vessel through an upperport, means for agitating ore pulp in said vessel to mingle4 air therewith and for supplying pulp through said upper port into said separating box,` and y means for subjecting said pulp to the action of an uprising current 'of air bubbles in said separating box.

5. In a device of the class described, anl

agitation vessel for ore pulp contained therein, a separating box communicating with said vessel through upper and lower ports, agitating and impelling means in said vessel for agitating the ore pulp and for causing a p circulation of said pulp from said vessel'to said box through the upper port and back to said vessel through the lower port, means for l introducing air in a n'ely'divided condition into the ore pulp in said separating box, sald box having an overow lip below the level of'said upper port, an outlet having a` capacity less than the supply-of pulp to said apparatus, and a second pulp outlet above said first-named outlet for regulating the level of the pulp in said box. Y

6. In a concentrating apparatus, an agitationvessel and separating box communicating with each other through-two ports, means for feeding pulp to said apparatus and for discharging the same therefrom, means for agitating said pulp and for impelling it from Said agitation vessel to said',l separating box at a more rapid rate than apparatus, thereby setting up a local circulation of pulp through said vessel,A box, and connecting orts, and means f or introducing the pulp is fed to and discharged from said air ina fine y divided condition into the ore".v y

pulp in said separatingA box. f 7. In a concentrating apparatus, a mixing vessel and a separating box having commum'- therein and thereby to cause said pulp to iow into said separating box through the upper port, and means for introducing air in a finely divided condition into the pulp in said separating box.

8. In a concentrating apparatus, a mixingv vessel and a separating box having communicating ports at points adjacent the top and bottom thereof, a rotary agitator in said vessel adapted by centrifugal force to elevate an ore pulp contained therein and thereby'to cause said pulp to flow into said separating box through the upper port, and means for introducing air in a finely divided condition into the pulp in said `separating box, said separating box having an .overflow lip below the level of the port at the top of said vessel.

9. In a concentrating apparatus, a mixing vessel and a separatingbox having communicating ports at points'ja'djacent the top and bottom thereof, a rotary agitator in said vessel adapted by centrifu al forcer to elevate an ore pulp Contained t erein and thereby to cause said pulp to flow into said separating box through the upper port, and' means for introducing air in a inely divided co1 .di-

tion into the pulp in said separating box,

said-box having a discharge outlet in its lower portion of a capacity less than that of the agitator, therebycausing a flow through said lower port. A -v 10. In a device of the class described, an agitation vessel for ore pulp contained therein, aseparating box communicating with said vessel through upper and lower ports,l

agitating and impelling means in said vessel for agitating the ore pulp and for causing a circulation of said pulp from said vessel to said box through the upperport and back to said vessel through the lower port, and means for introducing air in a inely divided conditioninto the ore pulp in said separating box, said box having an outlet in its lower portion of a capacity less than said upper port.

11. In a agitation vessel for ore pulp contained therein, a separating box located adjacent ,said agitation vessel, means for agitating said ore pulp in said vessel and minglin'g'air therewith and for discharging said pulp over the upper end of said vessel, means for receiving the pulp discharged over the upper end of said vessel and conveying the same into the upper part of said separating box, a permeable medium located in said separating box and inclined olov'vnwardlyl from the point where said pulp enters said box, means for supplying air .throu h said permeable medium, and means exten ing bedevice of the'class described, an

neath said permeable medium 'for conveying a portion of the pulp discharged into said box back into the lower part of said agitation vessel. x

12. In a concentrating apparatus, an agitation vessel and separating box having communication with each other at the upper and lower parts thereof, means in said vessel for agitating an ore pulp in contact with air and moving it in a circuit through said vessel and said `boxwhereby it is subjected to alternate periods of agitation in .said vessel and of substantial quiescence in said box, and means for introduclng air 1n a finely divided condition into the pulp' in said box.

13. In a concentrating apparatus, an agitation vessel vand separating box having communication with each other, means in said vessel for agitating an ore pulp in contact with air and causing a circulation of said pulp through said vessel Vand box,'and

means for introducing air in a finely divided condition into the pulp in said box, said `means comprising a perforated medium having an inclined position in said box leading downwardly from that part of said box below the outlet from said vessel.

14. In a concentrating apparatus, an agitation vessel and separating `box having communication with each other, lmeans in said vessel for agitating an ore pulp in contact with air and causing a circulation of said pulp through said vessel and box, means for introducingair in a finely divided condition into the pulp in said box, said means comprising a perforated medium having an inclinedposition in saidv box leading downwardly from that part of said box below the outlet from said vessel, said air-introducing means bein divided into independent portions at di erent depths, and means for. controlling the lair supply to each'of said portions. 15.' In a concentrating apparatus, an aglv-tation vessel and separating 4box havingcommunication with each other, means 1n .-said vessel for agitating an ore pulp in contact with air and causing a circulation of saidl pulp'through said vessel andbox, means for introducing #air in a finely dlvided condition into the pulp in said box, said means comprlslng a perforated medium having an inclined position in said box leading downwardly from that part of said box below the outlet .from said vessel, said box having an outlet below said air-introducing means of a capacity less than the circulating capacity of said agitating'means, and a second outlet of unrestricted capacity above said air-1ntroducing means.

16. In a device of the vclass described, an agitation vessel, andY a separating box having communication with each other through upper and lower ports, a mechanical agitator in said vessel for agitating ore pulpin contact with air and moving it in a circuit through said vessel and said box and said communicating ports, whereby it is subjected to alternate periods of agitation in said vessel and of substantial qulescence in said box, and means for introducing air in a finely divided condition into the pulp in said box.

17. In a concentrating apparatus, aseparating box, means for introducing air in a finely divided condition into' the ore pulp in said box, means for supplyin' a stream of pulp to said box, said box havlng an outlet of smaller capacity than said supplying means and said outlet being below the level of the air-introducing means, and a second outlet of unrestricted capacity leading from a point below to a point above the level-fof said air-introducing means, said second outlet being adjustable in height.

18. In a concentrating apparatus, a separating box, means for mtroducing air in a finelyv divided condition into the ore pulp in 'said box, means for supplying a stream of pulp to said box, said box having an out- 'let of smaller capacity than the suppl ing means and/said outlet being below the evel of the air-introducing means, a second outlet of unrestricted capacity above the level of the air-introducing means, said second outlet being adjustable in height, and an overflow lip above the level of said second outlet.

19. In a flotation apparatus, the combina'- tion of an upright conduit provided with means for admitting ore pulp at its lower Iportion and having an overiow at its upper portion; a perforated medium adapted to receive said overflow; means for mechanically agitating the ore pulp within said conduit and discharging it with a swirling motion upon said perforated medium; and means for forcing air through said perforated medium and into the pulp thereon, substantially as set forth. 20. In a device of theV class described, .an agitation vessel for ore pulp contained therein, a separating box communicating directly with said vessel through upper and lower ports, agitating and impelling means 1n said vessel or a 'tating the ore pulp and for causing a circ ationof said pulp from said vessel yto said box through the upper ort and back to the vessel through the ower port, and means for introducing air in a finely divided condition into the ore pulp in said separating box. 21. In aconcentrating apparatus, an agitation vessel and separatin box communi- .cating directly withk each ot er through two ports, means forfeeding pul to said apparatus and for dischar g t e same therefrom, V'means for agitatmg said pulp and for impelling it from said agitation vessel to said separating box at a more rapid rate that the pulp is fedto and discharged from said apparatus, thereby setting up a local circulation of pulp throu h said vessel, box, and connecting orts, an means for intro-. ducing air in a nely divided condition into the ore pulp in said separating box.

22. In a concentrating apparatus, a vmixing vessel anda separating box havingdirectly communicating ports at points adjacent the top and bottom thereof, a rotar agitator in saidv vessel adapted by centri 'ugal force to elevatean ore pulp Vcontained therein and thereby to cause said pulp to flow into said separatin lbox through the upper port, and means or introducing air in a finely divided condition into the pulp in said separating box.

23.- In a concentrating apparatus, an agitation vessel and separating box having direct communication with each other at the upper and"lower parts thereof, means in said vessel for agitatingan ore pulp in contact with `air and.mov 1ng it in a circuit.

through said vesseland said box, whereby it is subjected toV alternate periods 'of agitation in said 'vessel and of substantial quiesence in said box, and means for introducing air in a finely divided condition into the pulp in said box. p

24. In a concentrating. apparatus, an agitation vessel and separating box having direct communication with each other, means' in said vessel forl agitating an orepulp in c contact with air and causing a circulation of said pulp through said vessel and box, and means for introducing air in a finely divided condition into thepulp in said box, said means comprising a perforated medium having an'l inclined position in lsaid box leading downwardly from that part of said box below the -outlet from said vessel.

25. The combination in flotation apparatus for ore pulp, of an upright agitation vessel open at its upper end, a separatin box located'adjacent to andat one side o said vessel, a rotary agitator in said vessel -adapted to mingle air with pulp, means for conveying the overow f romtheupper end of sald vessel directly to said separating box, and means for -introducing air in a finely divided condition into the substantially uiescent pulp in said separating box.

26. he comblnation in flotation apparatus for ore pulp, of an'agitation vessel and a separating box formed as a unitary structure, a rotary agitator in said vessel for beating air into said pulp, a communicating port through which the'contents of said vessel pass to said separating box, and means for introducing air in a finely divided condi: tion into the pulp' in said separating box.

27. The combination in flotation apparatus for ore' pulp, of .an agitation vessel and a separating box formed as a unitary-structure, a frotary agitator in said vessel for beating air into said pulp, a communicating port through which the contents of said vessel pass to said separating box, means for introducin air in a finely divided condition into t e pulp in lsaid separatingbox, -and means for conveying a portion of the pulp from said separating box back to said agitation vessel.

28. The combination in flotation apparatus for ore pulp, of an upright agitation vessel and a separating box mounted adjacent each other and communicating directly through an upper port, a vertical shaft mounted in said vessel, agitating blades carried by said shaft, means for introducing through said porous medium, and means for 20 operating said shaft and thereby agitating said pulp and mingling air therewith in said Vessel and impelling said pulp through said .upper port into said separating box. l

In testimony whereof, I have subscribed 25 my name.

THOMAS A. JANNEY.

Witnesses A. FENN,

' GEO. A. TAYLOR. 

